Ostensibly the Commons was debating whether there should be an inquiry into the Iraq invasion. In fact, as so often when both sides are wrong, it turned into a party political food fight.

William Hague kicked off, but it was Simon Hughes who set the tone by demanding that an inquiry also looked at the role of the Tory party before the war.

Labour's Mike Gapes asked sarcastically whether the inquiry might also look at the sale of arms to Saddam by Margaret Thatcher - "or does it just start with the election of a Labour government?"

Ken Clarke believed that most MPs wanted an inquiry. He wanted to draw Labour backbenchers into a cross-party coalition to stiff the government. So they were all knifing each other in turn. The house resembled one of those Greek friezes in which everyone sticks a sword into the bloke in front, while the one behind returns the favour.

The government says that it doesn't feel there should be an inquiry while our brave lads are still in action. But everyone knows this translates as "an inquiry might find that the troops are there because of our spin, manipulation and outright lies, and then where would we be?"

The Tories take the view that there are plenty of precedents for inquiries being held while fighting continues. The result was a series of slightly mad interventions about the Dardanelles disaster in the first world war, the Norway disaster in the second world war, and more than one disaster in Mesopotamia, which of course is the old name for Iraq. Apparently they held inquiries then like Gordon Brown has reviews (did you know there is one on sunbeds, though not yet on Iraq?)

I half expected some Tory backbencher to declare solemnly that the formal inquiry into the Norman invasion had begun before King Harold had even hit the ground.

William Hague had assembled an invasion force of rhetorical phrases. We could not possibly hope to make a success of the future without understanding the past. The notion that the stability of Iraq or its economy would be affected by an inquiry was "ludicrous". The idea that our troops would be affected was "truly laughable".

"The morale of these wonderful people is made of far stronger stuff than that. They, above all others, want to know that we as politicians have learned from our mistakes - for which some of them have paid with their lives," he said.

It was a powerful and evocative statement. What a shame it was more or less destroyed when the foreign secretary, David Miliband, pointed out that as recently as October 2006, Mr Hague had said this was no time for an inquiry. It would be premature. "He said 'major policy decisions appear to be in the balance.' So they are today," added Mr Miliband.

Mr Hague sat uncomfortably listening to this, his finger jammed pensively into his cheek. The only thing that might have cheered him up was when Mr Miliband came close to admitting that the whole thing had indeed been another disaster.

"The building of the peace has gone much worse than people expected ... the mission has not yet been accomplished."

Well worth an inquiry, I'd say. We might even get it in a decade or so.